fix(retry): handle Retry-After date and align review nits

pkg/providers/error_classifier_test.go

@@ -139,8 +139,10 @@ func TestClassifyError_TimeoutPatterns(t *testing.T) {
 		"connection timed out",
 		"deadline exceeded",
 		"context deadline exceeded",
+		"connection reset",
 		"connection reset by peer",
 		"tls handshake timeout",
+		"EOF",
 	}
 
 	for _, msg := range patterns {

pkg/utils/llm_retry.go

@@ -43,7 +43,7 @@ type RetryPolicy struct {
 	Jitter          RetryJitterFunc
 }
 
-var retryAfterPattern = regexp.MustCompile(`(?i)retry[- ]after[:=]?\s*([^\s\r\n]+)`)
+var retryAfterPattern = regexp.MustCompile(`(?i)retry[- ]after[:=]?\s*([^\r\n]+)`)
 
 // DefaultLLMRetryPolicy returns the default retry behavior for LLM calls.
 func DefaultLLMRetryPolicy() RetryPolicy {
@@ -101,7 +101,7 @@ func DoWithRetry[T any](ctx context.Context, policy RetryPolicy, fn func(context
 
 	sleepFn := policy.Sleep
 	if sleepFn == nil {
-		sleepFn = sleepWithContext
+		sleepFn = sleepWithCtx
 	}
 	jitterFn := policy.Jitter
 	if jitterFn == nil {
@@ -232,18 +232,6 @@ func boundedAttemptTimeout(ctx context.Context, configured time.Duration) (time.
 	return configured, true
 }
 
-func sleepWithContext(ctx context.Context, d time.Duration) error {
-	timer := time.NewTimer(d)
-	defer timer.Stop()
-
-	select {
-	case <-ctx.Done():
-		return ctx.Err()
-	case <-timer.C:
-		return nil
-	}
-}
-
 func defaultJitter(max time.Duration) time.Duration {
 	if max <= 0 {
 		return 0

pkg/utils/llm_retry_test.go

@@ -150,3 +150,16 @@ func TestLLMRetry_DoWithRetry_UsesRetryAfterFor429(t *testing.T) {
 		t.Fatalf("slept = %v, want 3s", slept)
 	}
 }
+
+func TestLLMRetry_ExtractRetryAfter_HTTPDate(t *testing.T) {
+	now := time.Date(2015, 10, 21, 7, 27, 0, 0, time.UTC)
+	err := errors.New("API request failed:\n  Status: 429\n  Retry-After: Wed, 21 Oct 2015 07:28:00 GMT")
+
+	delay, ok := extractRetryAfter(err, now)
+	if !ok {
+		t.Fatal("expected retry-after date to parse")
+	}
+	if delay != time.Minute {
+		t.Fatalf("delay = %v, want 1m", delay)
+	}
+}